To zoom out when I am somewhere in Google Earth away from my home location (that Google knows), having placed the A3 pointer on the 'home' button above the Streetview button, I press the A3 central button with an Android symbol on it once and wait a second or two, and then when it zooms out and I have reached the right height above the map, with the pointer somewhere with no place names or symbols on the map, I click the central button twice to stop it zooming out.
When I replaced my router last year, it took a week or so for Google to relearn my location, but I just clicked on somehere hundreds of miles away on my list of Google Earth previous searches/more recent searches to zoom out until Google relearnt my location, as I do if I wish to zoom out when the map is centered on my home location.
PS. Have just read and mastered CybeRider's method, much better than mine, many thanks CybeRider.